genode/repos/os/include/nic/component.h

/*
 * \brief  Server::Entrypoint based NIC session component
 * \author Norman Feske
 * \author Sebastian Sumpf
 * \date   2015-06-22
 */

/*
 * Copyright (C) 2015 Genode Labs GmbH
 *
 * This file is part of the Genode OS framework, which is distributed
 * under the terms of the GNU General Public License version 2.
 */

#ifndef _INCLUDE__NIC__COMPONENT_H_
#define _INCLUDE__NIC__COMPONENT_H_

#include <os/attached_ram_dataspace.h>
#include <os/server.h>
#include <nic/packet_allocator.h>
#include <nic_session/rpc_object.h>

namespace Nic {

	class Communication_buffers;
	class Session_component;
}


class Nic::Communication_buffers
{
	protected:

		Nic::Packet_allocator          _rx_packet_alloc;
		Genode::Attached_ram_dataspace _tx_ds, _rx_ds;

		Communication_buffers(Genode::Allocator &rx_block_md_alloc,
		                      Genode::Ram_session &ram_session,
		                      Genode::size_t tx_size, Genode::size_t rx_size)
		:
			_rx_packet_alloc(&rx_block_md_alloc),
			_tx_ds(&ram_session, tx_size),
			_rx_ds(&ram_session, rx_size)
		{ }
};


class Nic::Session_component : Communication_buffers, public Session_rpc_object
{
	protected:

		Server::Entrypoint               &_ep;
		Genode::Signal_context_capability _link_state_sigh;


		/**
		 * Signal link-state change to client
		 */
		void _link_state_changed()
		{
			if (_link_state_sigh.valid())
				Genode::Signal_transmitter(_link_state_sigh).submit();
		}

		/**
		 * Sub-classes must implement this function, it is called upon all
		 * packet-stream signals.
		 */
		virtual void _handle_packet_stream() = 0;

		void _dispatch(unsigned) { _handle_packet_stream(); }

		Genode::Signal_rpc_member<Session_component> _packet_stream_dispatcher {
			_ep, *this, &Session_component::_dispatch };

	public:

		/**
		 * Constructor
		 *
		 * \param tx_buf_size        buffer size for tx channel
		 * \param rx_buf_size        buffer size for rx channel
		 * \param rx_block_md_alloc  backing store of the meta data of the
		 *                           rx block allocator
		 * \param ram_session        RAM session to allocate tx and rx buffers
		 * \param ep                 entry point used for packet stream
		 *                           channels
		 */
		Session_component(Genode::size_t const tx_buf_size,
		                  Genode::size_t const rx_buf_size,
		                  Genode::Allocator   &rx_block_md_alloc,
		                  Genode::Ram_session &ram_session,
		                  Server::Entrypoint  &ep)
		:
			Communication_buffers(rx_block_md_alloc, ram_session,
			                      tx_buf_size, rx_buf_size),
			Session_rpc_object(_tx_ds.cap(),
			                   _rx_ds.cap(),
			                  &_rx_packet_alloc, ep.rpc_ep()),
			_ep(ep)
		{
			/* install data-flow signal handlers for both packet streams */
			_tx.sigh_ready_to_ack(_packet_stream_dispatcher);
			_tx.sigh_packet_avail(_packet_stream_dispatcher);
			_rx.sigh_ready_to_submit(_packet_stream_dispatcher);
			_rx.sigh_ack_avail(_packet_stream_dispatcher);
		}

		void link_state_sigh(Genode::Signal_context_capability sigh)
		{
			_link_state_sigh = sigh;
		}

		/**
		 * Return the current link state
		 */
		virtual bool link_state() = 0;

		/**
		 * Return the MAC address of the device
		 */
		virtual Mac_address mac_address() = 0;
};


#endif /* _INCLUDE__NIC__COMPONENT_H_ */